JSFiddle - React, Tailwind, and code Playground

HTML

<div class="big">
    <div class="small"></div>
    
    
</div>

CSS

.big{
    background-color:red;
    width:400px; height:400px;
    
}
.small{
    float:left; position:absolute;
    background-color:blue;
    width:200px; height:200px;
    margin-left:300px;
    z-index:-1;
}